202 A NATURALIST IN BORNEO 



tion of ants with these plants has played at least a 

 small part in the development of the pitchers, and 

 some observations of Mr. H. H. W. Pearson 1 on 

 Dischidia shelfordi deserve consideration. In this 

 species the pitchers are double, that is to say, a small 

 pitcher is found inside each large pitcher. The large 

 pitchers are kidney-shaped, and are borne on very 

 short petioles ; the entrance to them is a small round 

 orifice just under the petiolar attachment, and it lies 

 at the bottom of a funnel-shaped depression. If a 

 pitcher be cut open it will be seen that the interior is 

 filled with numbers of rootlets, which springing from 

 the petiole or stem grow through the orifice of the 

 pitcher. The inner pitcher is formed by the inflexed 

 margin of the outer pitcher, the infolding taking 

 place in the funnel-shaped depression opposite to the 

 insertion of the petiole, it is therefore of the nature of 

 a pouch or pocket, and its walls are thickly beset with 

 small glandular hairs. In the large outer pitchers, in 

 addition to the rootlets are found a certain amount of 

 earth and numbers of ants Cremastogaster difformis. 2 

 In the inner pitcher of a species from the Philippines, 

 Mr. Pearson found a number of small irregularly 

 shaped masses sweet to the taste, and he came to the 

 conclusion that they were decomposition products of 

 cells in the neck of the inner pitcher, brought about 

 by punctures of ants, and the growth of fungi from 

 these wounds. Moreover, microscopic examination of 

 the inner surface of the outer pitcher revealed the 

 presence of a " dense waft of superficial mycelium," 



1 Journ. Linn. Soc. BoL, XXXV. (1901-4), p. 375. 



2 In another undescribed Bornean Dischidia with double pitchers, 

 a species of Dolichaderus (probably D. bituberculatus) has been found. 



